I just came back from the UK/Belgium a couple of weeks ago so I'm getting a kick from these replies. I had 43 different beers in the course of the trip, it was AMAZING!
I can heartily recommend any pub that is CAMRA recommended, My favorite was The Fleece Inn,
the pub-iest pub in all of pubdom. At the Fleece I had three amazing real ales, The Kings Schilling, UBU, and Pigs Ear. The best part of all these pubs was the variety. Every place we walked into had a different line up of beers, mostly local and lots of stuff we'll never see over here.
Special thanks to SWMBO for being DD and enduring my quest!